Question

Please answer this correctly

Answer 1

So if we know the perimeter of the circle we can find it's radius using the formula for perimeter:

$p = 2\pi(r)$

So we can solve for radius:

$r = \frac{10.71}{2\pi}$

Then we can plug this radius into the formula for the area of a circle:

$a = \pi {r}^{2}$

$a = \pi( \frac{10.71}{2\pi} ) ^{2}$

Then it only wants a quarter of that area so we divide that value by 4 which upon simplification becomes the answer:

$2.28 {ft}^{2}$

Answer 2

Answer:

$\boxed{Area \: of \: quarter \: circle = 7.065 \: square \: feet}$

Given:

Perimeter of quarter circle = 10.71 feet

To find:

Area of quarter circle

Step-by-step explanation:

First we need to calculate the radius of quarter circle:

Let the radius of quarter circle be 'r'

$Perimeter \: of \: quarter \: circle = \frac{\pi r}{2} + 2r$

$\implies 10.71 = \frac{\pi r}{2} + 2r \\ \\ \implies 10.71 = \frac{\pi r}{2} +2r \frac{2}{2} \\ \\ \implies 10.71 = \frac{\pi r}{2} + \frac{4r}{2} \\ \\ \implies 10.71 = \frac{\pi r + 4r}{2} \\ \\ \implies 10.71 \times 2 = \pi r + 4r \\ \\ \implies 21.42 = \pi r + 4r \\ \\ \implies 21.42 = (\pi + 4)r \\ \\ \implies 21.42 = (3.14 + 4)r \\ \\ \implies 21.42 = 7.14r \\ \\ \implies 7.14r = 21.42 \\ \\ \implies r = \frac{21.42}{7.14} \\ \\ \implies r = 3 \: ft$

$Area \: of \: quarter \: circle = \frac{\pi {r}^{2} }{4} \\ \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = \frac{\pi \times {(3)}^{2} }{4} \\ \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = \frac{\pi \times 9}{4} \\ \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = \frac{3.14 \times 9}{4} \\ \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = \frac{28.26}{4} \\ \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: =7.065 \: {ft}^{2}$